transfer any clumps to a separate tube, add Buffer P1 and mix vigorously for resuspension, add Buffer P2 for lysis, and subsequently transfer the lysed material back to combine it with the rest of the original solution

Note: Avoid incubation times longer than 5 minutes in Buffer P2 as this will irreversibly denature plasmid DNA. In the scenario above, Buffer P3 may need to be added to portions of the sample, which can be subsequently combined once resuspension, lysis and neutralization of all fractions is complete.